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Product overview

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Dishwashing liquids

15mar dishwashing liquids hero default

Washing up the old-fashioned way.

We’ve compared 12 dishwashing liquids, including a home recipe, to discover which is best for powering through your dirty dishes.

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About our test

Would you trust a detergent that had no foam? While dishwashing liquids often have plenty of the chemicals that create bubbly foam, it’s a detergent’s surfactants that are actually responsible for its cleaning. Surfactants break down the interface between the object being cleaned and dirt, oils and water. They lift the dirt and oils away, suspending them in the water.

The plates in our sink are pre-soiled with a combination of oils, milk powder, gravy, flour, vegetable stock and carbon, to simulate common stains. We wash the plates using a mechanical scrubbing arm, using 5ml of detergent in a 5L sink. Reflectiveness is measured before and after scrubbing with a spectrophotometer. Each detergent is tested 8 times with the average used as the final performance score.

Some of the detergents in our test come in various pack sizes and fragrances. These have no effect on performance.

Claims

Dishwashing liquids often have claims, such as “cruelty free” and “gentle on hands”, on the bottle. We’ve listed some of these claims in our product comparisons, but haven't tested them:

Surfactants are biodegradable Surfactants can have adverse effects on the environment, but “biodegradable” ones will break down and have little effect. There is an Australian standard, AS4351, that some manufacturers may follow, but this only applies to the surfactants. There are no guarantees the other ingredients in the product are biodegradable.

Safe for septic tanks If you have a septic tank, it can be hard finding household cleaners that are safe to flush down the drain. Cleaners often contain harsh chemicals that can damage a septic tank. We suggest contacting your septic tank manufacturer to see what it recommends.

Gentle on hands There is no way of testing this claim as everyone’s skin reacts differently to chemicals.

The wastewater (grey water) is safe This means the waste, or “grey”, water is safe for other uses, such as watering the garden. If you are using grey water in your garden, we suggest not using it on your vegetables.

Cruelty free Indicates the product wasn’t tested on animals. This claim only relates to the exact product and won’t cover any historical testing of the detergent or any of its ingredients. It’s best to look for a product that has been verified by a third-party scheme, such as Cruelty Free International or Choose Cruelty Free.

Made from plant-based ingredients This claim may only apply to some ingredients in the detergent, and may not mean the entire product is made from plant-based products. There’s no standard against which to measure these claims.

Phosphate free Usually listed on laundry detergents, this claim is best accompanied by a minimum phosphate percentage, such as with laundry detergents. We found dishwashing liquids claiming to be phosphate-free, but we couldn’t find any stated phosphate percentages. See our article on unfair green claims for about phosphates in dishwashing liquids.

Kosher certified This means the ingredients and production of the product are in line with the Jewish faith. This claim is usually accompanied by the symbol of a third party scheme.

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